nanog mailing list archives
Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems
From: William Herrin <bill () herrin us>
Date: Sat, 27 Aug 2022 19:16:04 -0700
On Sat, Aug 27, 2022 at 12:00 PM Sean Donelan <sean () donelan com> wrote:
In some situations where a client machine is connected via some specific Optical Network Terminals (ONTs), and data is appended after the packet checksum, the network adapter can drop receive packets when using TCP-IPv6 Checksum Offload for receive traffic.
Hi Sean, Do you happen to have any details on the bug? I note that the IPv6 header DOES NOT HAVE a checksum; it relies on the checksum in the layer-2 frame. I'm not clear how you "append" bytes to the ethernet frame "after" calculating the checksum, have the hardware checksum fail but have the software checksum succeed. Regards, Bill Herrin -- For hire. https://bill.herrin.us/resume/
Current thread:
- VZ FIOS and Intel TCP IPv6 Checksum Offload problems Sean Donelan (Aug 27)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Michael Thomas (Aug 27)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Mel Beckman (Aug 27)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Michael Thomas (Aug 27)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Sean Donelan (Aug 29)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Christopher Morrow (Aug 29)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Brie (Aug 29)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Niels Bakker (Aug 29)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Mel Beckman (Aug 27)
- Re: VZ FIOS and Intel TCP IPv6 Checksum Offload problems Michael Thomas (Aug 27)